Knitting machines

ABSTRACT

A sinker for a knitting machine with independently operable needles, has a curved edge for sliding engagement with a supporting structure in a knitting machine, a hook for engaging and pushing down knitted loops, a nose extending forward of the open mouth of the hook and presenting an edge to support knitted loops for engagement by the hook, and a raised edge extending rearwardly from the point of the hook. A knitting machine comprising such a sinker and a method of operating the machine are also described.

[ 73] Assignee: Courtaulds Limited, London, En-

gland [22] Filedz' Dec. 10, 1970 [21] Appl.No.: 96,728

[52] U.S.Cl ..66/l04, 66/109 [51] llnt.Cl. ..D04b1l5/06 [58] Field ofSearch ..66/ 104, 109,75, 66/64, 60, 106, 107, I08

[5 6] References Cited I UNITED STATES PATENTS 3,293,887 12/1966 Crawford"; ..66/lO8 3,283,542 11/1966 Nebeletal. ..66/108 616,601 12/1898 Burson ..66/109 819,407 5/1906 Burson ..66/75X 37 WW 15s 152/ 1 2 1i 4 16 a; 35' i,\ \aa 32" I 74 4 Mute tates atent H 1 [11] egan Flavell et al. [451 lay 29, 1973 [54] KNITTING MACHINES 3,293,886 12/1966 Nebel ..66/l04 x Inventors: John Flavell; Max William Betts, I

both of Coventry; Frank Robinson, FOREIGN PATENTS Oil APPLICATIONS Borrowash, all of England 261,092 4/1968 Austria ..66/108 Primary Examiner-Ronald Feldbaum Att0rney--Davis, Hoxie, Faithful] & l-lapgood 5 7 ABSTRACT A sinker for a knitting machine with independently operable needles, has a curt/ed edge for sliding engagement with a supporting structure in a knitting machine, a hook for engaging and pushing down knitted loops, a nose extending forward of the open mouth of the hook and presenting an edge to support knitted loops for engagement by the hook, and a raised edge extending rearwardly from the point of the hook. A knitting machine comprising such a sinker and a method of operating the machine are also described.

16 Claims, 5 Drawing Figures PATENTEW 3,735,812

SHEET 1 OF 2 JH/V FLAVEL x WILL/RM BETTS HNK ROB/N504 INVENTO 5y wm 9M w l ATTORNEY KNITTING MACHINES This invention is concerned with a sinker for knitting machines having independently operable needles. Sinkers are flat members interdigitated with the needles in a knitting machine and serving to provide edges over which loops of yarn are drawn when the needles descend. The present sinker serves also as a web-holding sinker, that is, it is shaped to engage knitted loops and can be moved to push these loops down with respect to the needles.

In a flat knitting machine having movable sinkers in two beds arranged opposite one another it has been necessary, in order to avoid opposite sinkers clashing when one of them moves, to have the opposite beds spaced a relatively wide distance apart. When carrying out tubular knitting in flat machines with two beds a flattened tube is formed, the edge stitches of which extend between the two beds and if the beds are spaced more widely than the gauge of the needles these edge stitches will be larger than the stitches formed. along the beds giving an undesirable appearance to the edges of the tube. I

The present invention aims to provide a sinker for a knitting machine with independently operable needles which leads to avoidance of the difficulty mentioned above.

According to one aspectof the invention, a sinker for a knitting machine with independently operable needles, has a body with acurved edgefor sliding engagement with a supporting structure in a knittingmachine, a hook extending from the body for engaging and pushing down knitted loops, a nose extending forwardly of the open mouth of the hook andpresenting an edge to support knitted loops for engagement by the hook, and

- a raised edge extending rearwardly from the point of the hook.

According to a further aspect of the invention a knitting machine with independently operable needles incorporates sinkers of the form just described. In a knit ting machine according to the invention, the sinkers are shaped to move in such a way that the beds can belocated relatively close together without fear of the sinkers clashing. Yet another aspect of .the invention consists in operating a knitting machine of the kind just described in such a manner as to draw a loop over the said raised edge of a sinker, thereafter retracting thesinker thereby causing the loop to fall onto the nose of the sinker, moving the associated needles'further down to reduce the slackness in the loop on the nose, and then moving the sinker forward once more to push the loop on the nose downwardly with'respect to the needle beds.

The means causing movement of the needles may be arranged to cause or allow upward movement of the needle during retraction of the sinker and before the needles are moved further down.

The said curved edge on the sinker is advantageously a circular arc. Thesinker may comprise a body having the shape of part of an annulus and a butt may be provided on the body for engagement by a jack having a butt engageable in a cam track in a cam box arranged to traverse the needle beds with the cam box which operates the needles, whereby the sinker can be moved forwardly and rearwardly.

The invention will be further described, by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a side view of a sinker according to the invention,

FIG. 2 is a section through the needle beds of a V-bed knitting machine according to the invention,

FIG. 3 is a diagram showing the position of a sinker cam and a stitch cam in the machine of FIG. 2, and

FIGS. 4 and 5 are cross-sections through one of the needle beds of FIG. 2 showing successive positions of a sinker during the knitting cycle.

The sinker shown in FIG. 1 comprises a body 6 constituting part of an annulus. The edge 7 of the body has the form of a circular are centered at the point A. A

' raised portion 8 of the body on theedge opposite the parts of the body and extends rearwardly from the point of the hook 9. The edge 13 is a circular arc with its center at B and this edge thus approaches closer to the edge 7 in the forward direction of the sinker. A butt 14 having an outer edge 15 constituting part of a circle is formed on the body for engagement in the cam track of a cam box as will be described below.

In FIG. 2 are shown two parallel beds 16 and 17 of a V-bed knitting machine. Tricks accommodating an array of needles are formed in each bed and the needles are interdigitated with identical sinkers. A needle 20 is shown in a trick 18 formed in the bed 16 and a needle 21 is shown in a trick 19 formed in the bed 17. The needles in the beds are held in place by needle bands 24 and 25. Each needle has a butt 26 engaged by the head of a clavette 27 which is slidable in the same trick as the needle. Each clavette'27 has a butt (not shown in FIG. 2 but designated by the numeral 48in FIG. 3) engageable in a cam track 31 (FIG. 3) of a cam box (not shown) in the usual way to bring about sliding movement of the needles in the tricks.

Secured to the needle beds 16 and 17 are sinker jack beds 28 and 29 to which are secured further beds in which the sinkers 6 are located. The form and manner of mounting of the two sinker beds is identical and only the sinker bed associated with the needle bed 16 will be described. The sinker jack bed 28 has a groove 32 formed in an oblique face 30on one end of the sinker jack bed. The groove 32 extends in the longitudinal direction of the bed 16 and a ridge 33 on the sinker bed 34 is engaged in the groove 32. A series of tricks is formed in the sinker bed 34, a sinker being located in each trick. Aside wall 35 of one of the tricks is visible in FIG. 2. The floor 35' of each trick is curved and in the present machine has the form of a circular arc. The curved edge 7 of each sinker engages the floor 35' of its associated trick. A sinker jack retainer 36 carries a guide 37 having a head 38 in the form of a channel member, the edges 39 and 40 of the channel being located so as to maintain the sinkers 6 in their tricks.

Each sinker is associated with a jack by which the sinker is moved. A jack 43 associated with the sinker 6 shown in FIG. 2 is shown in the Figure. The jack has a forked head 44 engaged with the butt 15 on the sinker 6 and a butt 45 on the jack 43 is arranged for engagement in the cam track 46 (FIG. 3) of a cam box (not shown) for operating the sinkers.

The cam tracks for operating the needles and the sinkers are formed in cam boxes which are secured to one another for movement longitudinally of the needle beds. The tracks are shown diagrammatically in FIG. 3 where the butt 45 on the sinker jack is shown at the position identified by the chain lines 47 and the butt 48 on the clavette 27 is shown at the same position. When the two butts are in the positions shown in FIG. 3, the sinker 6 and the needle 20 shown in FIG. 2 will be located in the positions shown in that Figure.

In FIG. 2 the yarn 49 has been pulled into a loop over the raised edge 13 of the sinker 6 by the needle 20 and the adjacent needle (not shown) on the opposite side of the sinker. The yarn is shown forming a first course of knitting. The stitch cam and the sinker cam are moving to the right in FIG. 3 and the needle 20 has, therefore, previously been raised to take the yarn and has been retracted by the stitch cam to pull the loop over the raised edge 13 of the sinker 6 as shown. On further movement of the cams, the sinker 6 is retracted to the position shown in FIG. 4, so that the loop of yarn 49 drops as a loose loop on to the nose 12, this movement of the loop being facilitated by the narrowing of the distance between the raised edge 13 and the edge 7 in the forward direction of the sinkers. At the same time as this retraction of the sinker takes place, the butt on the clavette 27 controlling the needle comes under the influence of the portion 50 of the cam track 31. The portion 50 of the cam track allows the butt of the clavette to rise thus removing the downward force acting on the needle and allowing the needle to move upwardly to a small extent during the rearward movement of the sinker to allow rob of and to relieve the tension in the yarn. Thereafter, the clavette and needle are moved downwardly by the downwardly inclined part 51 of the portion 50 of the cam track acting on the butt of the clavette which is moved down to a lower position than before retraction of the sinker. Thus the loop of yarn 49, which has been loosened by being dropped onto the nose 12 is made tighter than it would have been if the needle remained stationary during retraction of the sinker. Thus, better control over the knitting is achieved. Thereafter, the sinker is again pushed forward as shown in FIG. and pushes the loop of yarn down away from the needles. The sinker is then maintained in this position until on the next traverse of the cams (which takes place in the opposite direction) the needle has been raised once more. Thus the sinker ensures by holding down the previously knitted loop in the hook 9, that the needle will rise through this loop of yarn. When on this next traverse of the cam the needle has gathered further yarn and has pulled a new loop over the edge 13, the sinker is again retracted, as in FIG. 4, and is then advanced once more to push down the new knitted loop.

On retraction of the sinker, since the previously formed loop 49, now resting on the nose 12, is loose on the nose, there is little tendency for this loop to be pulled up as the sinker nose moves up.

All the sinkers in the machine are shaped and arranged to operate in the manner described above.

Since the sinkers serve in this machine to push the knitting down away from the needles, the machine can operate without take down rollers. The machine is capable of carrying out the knitting of portions of fabric in which some needles are held up during the knitting process while knitting continues on adjacent needles.

As can be seen from FIG. 2, because the sinkers comprise part annular bodies and are mounted for movement on curved surfaces (the floors of the sinker bed tricks), they will not clash with sinkers opposite them even if opposite sinkers are moved simultaneously.

What is claimed is:

l. A sinker for a knitting machine with independently operable needles, said sinker comprising a body with a curved edge for sliding engagement with a supporting structure in a knitting machine, a hook extending from the body and having an open mouth for engaging and pushing down knitted loops, a nose extending forwardly of the open mouth of the hook and presenting an edge to support knitted loops for engagement by the hook, and a raised edge extending rearwardly from the point of the hook for a distance sufficient to accommodate a loop for knock over, said raised edge diverging from the curved edge of the sinker body in a direction rearward of the point of the hook so that a loop over the raised edge will slide off said raised edge onto the nose when the sinker is retracted.

2. A sinker as claimed in claim 1, in which the curved edge of the sinker body is defined by a circular arc.

3. A sinker as claimed in claim 2, in which the sinker body has the shape of part of an annulus, said curved edge being the edge of smaller radius of curvature of the part annular body.

4. A sinker as claimed in claim 3, in which said hook extends from the edge of larger radius of curvature of the part annular body.

5. A sinker as claimed in claim 3, in which said nose is formed by an end portion of the part annular body.

6. A sinker as claimed in claim 3, comprising a butt extending from the edge of larger radius of curvature of the part annular body.

7. A sinker as claimed in claim 3, in which said raised edge is defined by a circular arc.

8. A sinker as claimed in claim 7, in which the radial distance between said raised edge and the edge of smaller radius of curvature of the sinker body decreases in the direction towards the point of the hook.

9. A knitting machine with independently operable needles, the movements of which are controlled by cam box means, comprising a sinker as claimed in claim 1 located between two adjacent needles of a needle bed of the machine.

10. A V-bed knitting machine comprising independently operable needles in each needle bed, the movements of which needles are controlled by cam box means, and, between each pair of adjacent needles in each bed, a sinker as claimed in claim 1.

11. A knitting machine as claimed in claim 10, in which the or each sinker is movably mounted on its own trick in a sinker bed secured to the needle bed in which the pair of adjacent needles associated with the sinker are located.

12. A knitting machine as claimed in claim 11, in which the or each sinker is moved by an associated jack which in turn is controlled by said cam box means.

13. A method of operating a knitting machine having independently operable needles, the movements of which are controlled by cam box means, and a sinker between each pair of adjacent needles of a needle bed of the machine, each of said sinkers comprising a body with a curved edge for sliding engagement with a supporting structure in the knitting machine, a hook extending from the body and having an open mouth for engaging and pushing down knitted loops, a nose extending forwardly of the open mouth of the hook and presenting an edge to support knitted loops for engagement by the hook, and a raised edge extending rearwardly from the point of the hook for a distance sufficient to accommodate a loop for knock over, said raised edge diverging from the curved edge of the sinker body in a direction rearward of the point of the hook so that a loop over the raised'edge will slide off said raised edge onto the nose when the sinker is retracted, said method comprising the steps of drawing each loop formed on the machine over the said raised edge of a sinker, thereafter retracting the sinker thereby causing the loop to fall onto the nose of the sinker, moving the associated needles further down to reduce the slackness in the loop on the nose, and then moving the sinker forward once more and the sinker hook downwardly to push the loop on the nose downwardly with respect to the needle bed.

14. A knitting machine with independently operable needles comprising a sinker as claimed in claim 1,

means for drawing a loop over the raised edge of the for moving the sinker forward thereby causing the hook extending from the body of the sinker to engage and push down the loop on the nose of the sinker.

15. A knitting machine having a sinker as claimed in claim 1 located between two adjacent needles of a needle bed of the machine comprising means for drawing a loop over the raised edge of the sinker, means for retracti'ng the sinker thereby causing the loop to fall from the raised edge onto the nose of the sinker, and means for moving the sinker forward thereby causing the hook extending from the body of the sinker to engage and push down the loop on the nose of the sinker.

16. A knitting machine having a sinker as claimed in claim 1 located between two adjacent needles of a needle bed of the machine comprising means for retracting the adjacent needles to draw a loop over the raised edge of the sinker, means for retracting the sinker thereby causing the loop to fall from the raised edge onto the nose of the sinker, means for further retracting the adjacent needles to reduce the slackness in the loop on the nose, and means for moving the sinker forward thereby causing the hook extending from the body of the sinker to engage and push the loop on the nose of the sinker downwardly with respect to the needle bed.

Disclaimer 3,735,812.J07m Flowell and Max William Betts, Coventry, and Fmnlc Robinson, Borrowash, England. KNITTING MACHINES. Patent dated May 29, 1973. Disclaimer filed Aug. 18, 1978, by the assignee, Oouwzfaulds Ltd. Hereby enters this disclaimer to claims 1 to 16 inclusive of said patent.

[Ofiicz'al Gazette October 1'7, 1978.] 

1. A sinker for a knitting machine with independently operable needles, said sinker comprising a body with a curved edge for sliding engagement with a supporting structure in a knitting machine, a hook extending from the body and having an open mouth for engaging and pushing down knitted loops, a nose extending forwardly of the open mouth of the hook and presenting an edge to support knitted loops for engagement by the hook, and a raised edge extending rearwardly from the point of the hook for a distance sufficient to accommodate a loop for knock over, said raised edge diverging from the curved edge of the sinker body in a direction rearward of the point of the hook so that a loop over the raised edge will slide off said raised edge onto the nose when the sinker is retracted.
 2. A sinker as claimed in claim 1, in which the curved edge of the sinker body is defined by a circular arc.
 3. A sinker as claimed in claim 2, in which the sinker body has the shape of part of an annulus, said curved edge being the edge of smaller radius of curvature of the part annular body.
 4. A sinker as claimed in claim 3, in which said hook extends from the edge of larger radius of curvature of the part annular body.
 5. A sinker as claimed in claim 3, in which said nose is formed by an end portion of the part annular body.
 6. A sinker as claimed in claim 3, comprising a butt extending from the edge of larger radius of curvature of the part annular body.
 7. A sinker as claimed in claim 3, in which said raised edge is defined by a circular arc.
 8. A sinker as claimed in claim 7, in which the radial distance between said raised edge and the edge of smaller radius of curvature of the sinker body decreases in the direction towards the point of the hook.
 9. A knitting machine with independently operable needles, the movements of which are controlled by cam box means, comprising a sinker as claimed in claim 1 located between two adjacent needles of a needle bed of the machine.
 10. A V-bed knitting machine comprising independently operable needles in each needle bed, the movements of which needles are controlled by cam box means, and, between each pair of adjacent needles in each bed, a sinker as claimed in claim
 1. 11. A knitting machine as claimed in claim 10, in which the or each sinker is movably mounted on its own trick in a sinker bed secured to the needle bed in which the pair of adjacent needles associated with the sinker are located.
 12. A knitting machine as claimed in claim 11, in which the or each sinker is moved by an associated jack which in turn is controlled by said cam box means.
 13. A method of operating a knitting machine having independently operable needles, the movements of which are controlled by cam box means, and a sinker between each pair of adjacent needles of a needle bed of the machine, each of said sinkers comprising a body with a curved edge for sliding engagement with a supporting structure in the knitting machine, a hook extending from the body and having an open mouth for engaging and pushing down knitted loops, a nose extending forwardly of the open mouth of the hook and presenting an edge to support knitted loops for engagement by the hook, and a raised edge extending rearwardly from the point of the hook for a distance sufficient to accommodate a loop for knock over, said raised edge diverging from the curved edge of the sinker body in a direction rearward of the point of the hook so that a loop over the raised edge will slide off said raised edge onto the nose when the sinker is retracted, said method comprising the steps of drawing each loop formed on the machine over the said raised edge of a sinker, thereafter retracting the sinker thereby causing the loop to fall onto the nose of the sinker, moving the associated needles further down to reduce the slackness in the loop on the nose, and then moving the sinker forward once more and the sinker hook downwardly to push the loop on the nose downwardly with respect to the needle bed.
 14. A knitting machine with independently operable needles comprising a sinker as claimed in claim 1, means for drawing a loop over the raised edge of the sinker, means for retracting the sinker thereby causing the loop to fall onto the Nose of the sinker, and means for moving the sinker forward thereby causing the hook extending from the body of the sinker to engage and push down the loop on the nose of the sinker.
 15. A knitting machine having a sinker as claimed in claim 1 located between two adjacent needles of a needle bed of the machine comprising means for drawing a loop over the raised edge of the sinker, means for retracting the sinker thereby causing the loop to fall from the raised edge onto the nose of the sinker, and means for moving the sinker forward thereby causing the hook extending from the body of the sinker to engage and push down the loop on the nose of the sinker.
 16. A knitting machine having a sinker as claimed in claim 1 located between two adjacent needles of a needle bed of the machine comprising means for retracting the adjacent needles to draw a loop over the raised edge of the sinker, means for retracting the sinker thereby causing the loop to fall from the raised edge onto the nose of the sinker, means for further retracting the adjacent needles to reduce the slackness in the loop on the nose, and means for moving the sinker forward thereby causing the hook extending from the body of the sinker to engage and push the loop on the nose of the sinker downwardly with respect to the needle bed. 